Krista and Tatiana Hogan are Canadian conjoined twins who were born joined by their heads, which is a very rare case in medicine. The importance of the lives of these sisters to neuroscience is due to their ability to share the senses of each other through the brain.


Two girls, Krista and Tatiana Hogan, were born in 2006 in Vancouver, Canada, as conjoined twins. The doctors did not hope they would survive or be able to live active life due to a serious particularity – the babies were joined at the head. In medicine, such twins are called craniopagus twins and are born once in 2.5 million births. Despite the hopeless predictions of doctors who claimed that if the twins survived, they would be bed-ridden, Krista and Tatiana manage to live an active life with the great support of their parents.

The scientists’ attention is attracted to the girls due to their significant particularity. Indeed, they can see through each other’s eyes, hear through each other’s ears, and can share the senses of taste and touch. Moreover, Krista and Tatiana Hogan share thoughts and motor control. One of them controls one arm and three legs when the other controls three arms and one leg.

Such distinctive features make sisters Hogan’s case an important contribution to the development of neuroscience and the understanding of the human brain. The inseparable twins have fully developed hemispheres of brains. However, the area where the two brains are connected is presumably the one through which the neurons are transmitted. The fact that these twins survived contributes to the scope of knowledge about the human body and the role of the brain in it.